Data storage systems are arrangements of hardware and software that include storage processors coupled to arrays of non-volatile storage devices. In typical operation, storage processors service storage requests that arrive from a client. The storage processors run software that manages incoming storage requests and performs various data processing tasks to organize and secure the data stored on the non-volatile storage devices.
Some data storage systems have multiple IP addresses through which they serve multiple clients. When a storage processor receives a transmission from a client, the storage processor internally directs the transmission to the IP address specified in the transmission. Also, the storage processor may direct a reply to the same client at the client's IP address, which was specified in the transmission that the storage processor received from the client. The storage processor may look up routing information for locating the client from a routing table maintained in the storage processor's network stack. The information in the routing table includes an address of a gateway, which may reside in a local subnet to which a port of the storage processor is connected and which provides an interface to an additional network, such as a WAN or the Internet.